Power and energy, positive and negative

An attempt to clarify the definitions of power, power factor, and related quantities has led to an intensive study which has included a large number of actual test measurements of the quantities involved. Measurements of positive and negative power, and the use of a “power ratio” based upon these 2 quantities are proposed, particularly for circuits in which the voltages and currents are nonsinusoidal or unbalanced. Positive and negative energy and power can be measured approximately with apparatus commercially available.